victualling of the army and for the equipment of a regular medical service (Fœdera, ix. 436–7). Special attention was directed to the navy; ships were built by Henry's direction at Southampton and on the Thames, so that in February 1417 the king had six great ships, eight barges, and ten balingers (Nicolas, Agincourt, App. p. 212; see ‘Libel of English Policye’ in Pol. Songs, Rolls Ser. ii. 199–201; a longer list drawn up in August 1417 is given in Ellis, Letters, 3rd ser. i. 73; cf. also ib. 2nd ser. i. 67–72). These were royal vessels in addition to those supplied by the ports, and it is from this time that the foundation of the navy as a national force most probably dates (Nicolas, History of the Navy, vol. ii. chap. vi.). Furthermore, ordinances were issued for the fleets and armies which entitle Henry to be considered the founder of our military, international, and maritime law (ib. ii. 405–6; Agincourt, App. p. 31; Stubbs, Const. Hist. iii. 77). On 25 April 1417 Henry rode through London to St. Paul's and took his leave of the citizens (Cott. MS. Claud. A. viii. f. 5); he then went to Southampton and busied himself with the final preparations for departure.
On 23 July 1417 Henry's second expedition set sail with an army of nearly fifty thousand men in a fleet of sixteen hundred ships (Puiseux, Siège de Caen, p. 31). On 1 Aug. it disembarked on the south bank of the Seine near Touques. Master of Harfleur and the north of the Seine, a less skilful general might have been tempted to march straight on Rouen as the capital of northern France. Henry, however, displayed his generalship by a very different plan. The first campaign was devoted to securing the towns and castles of central Normandy, by which means the province was cut in half, Brittany and Anjou forced into neutrality (Fœdera, ix. 511–13), and the communications of Rouen with central France severed. The castles of Touques and D'Auvillars surrendered early in August; by a skilful march Henry cut off Caen from Honfleur, Rouen, and Paris, and by the 18th was able to invest the town, which promised to supply suitable winter quarters, and was too important to be left uncaptured in his rear (Puiseux, Siège de Caen, p. 33; Rel. de St.-Denys, xxxviii. 12; Livius, p. 35). On 4 Sept. the town was carried by assault, Henry directing the attack in person; the castle held out till the 19th. The work of conquest proceeded with startling rapidity. Bayeux, Alençon, Argentan, and many smaller places were surrendered after little or no resistance, so that by the middle of October the whole province up to Le Mans was secured. This success was no doubt assisted by the dissensions among the French, the Armagnacs having recalled their men-at-arms to employ them against the Burgundians (Barante, iii. 212; St.-Remy, i. 341). In October Henry went to direct the siege of Alençon, and at the end of the month held a conference there with the Duke of Brittany, who according to one account offered to hold Brittany as his vassal (Walsingham, Hist. Angl. ii. 326–7; Fœdera, ix. 505–6, 511). Towards the end of November he laid siege to Falaise; the town surrendered on 2 Jan. 1418 and the castle a month later. Except for a short visit to Caen in February, Henry remained in the neighbourhood of Falaise till the beginning of March 1418, when he went to Bayeux and spent Easter there; from 21 April till the end of May he was at Caen. During this time he took no active part in the war, which was, however, vigorously prosecuted by his lieutenants. Gloucester was despatched to the Cotentin and besieged Cherbourg in April, Huntingdon captured Coutances and Avranches, Warwick besieged Domfront, and Exeter Evreux, while Clarence was employed in preparing for the advance on Rouen, which was to be the main feature of the year's campaign. Henry, no doubt, gave a general superintendence while occupied at Caen with civil organisation and preparation for the siege of Rouen.
At the end of May Henry went to Bernay and joined Clarence, who had by this time captured Lisieux and most of the small towns of the Lieuvin. The capture of Louviers, 22 June, was followed on 20 July by that of Pont de l'Arche, which made the English masters of the Seine above Rouen (cf. Rel. St.-Denys xxxix. 10). After waiting for Warwick and Salisbury to join him, Henry left Pont de l'Arche on 29 July, and marching by the right bank of the Seine appeared before Rouen on the same day. His first task was to provide for the safety of his army by the construction of regular fortified lines. He himself took up his station at the Chartreuse de Notre Dame de la Rose, on the north of the Seine. The next work was to cut off Rouen from the sea, and to secure his own communications with Harfleur. In blockading the mouth of the Seine he was assisted by a fleet sent by his kinsman and ally the king of Portugal. Above the town he constructed a firmly built wooden bridge, a remarkable work, which was completed with great rapidity despite frequent attacks from the enemy. Henry thus secured the position of his own army, which was encamped on both sides of the Seine, while to further obstruct the navigation heavy chains were stretched across the stream. Rouen
